Objective: To investigate long-term consistency of spectral data features extracted from local field potential (LFP) recordings of the subthalamic nucleus (STN) in Parkinson’s disease (PD) patients chronically implanted with deep brain stimulation (DBS) electrodes.

Background: The development of adaptive DBS paradigms critically relies on the use of so-called “physiomarkers”, mostly extracted from LFP recordings. In PD, the most promising physiomarkers are LFP features related to beta oscillations (13-35 Hz) as they have consistently been found to correlate with the severity of contralateral rigidity and bradykinesia. However, the consistency of beta-based data features over time recorded with sensing-enabled neurostimulators is yet unknown.

Method: Bilateral STN-LFPs were recorded during 60s rest from nine subjects with chronically implanted DBS electrodes (7±2 years post-surgery). Due to battery depletion, the pulse generator was replaced with the Medtronic Percept^TM neurostimulator in a care as usual setting. Recordings were obtained at least at two different time points with an average inter-recording interval of 99±44 days. During each visit, recordings were conducted once with stimulation switched off (OFF) and once on stimulation (ON) with the patients’ clinically effective stimulation parameters. LFP beta band features were extracted from the relative power spectral densities and compared across time points.

Results: Beta peaks observed in LFPs OFF stimulation disappeared after turning the stimulation ON. The frequency, height, as well as width of these OFF-DBS beta peaks remained similar within each patient across time points, but differed between patients. As beta peaks disappeared whilst turning the stimulation ON,  a relative power shift towards lower spectral frequencies was observed (Figure). This finding was also consistent within subjects over time.

Conclusion: Our findings demonstrate that patient-specific beta-based features of STN-LFP recordings from fully implanted neurostimulators are consistent over time, allowing to further study the use of these features as physiomarkers for adaptive DBS.

« Back to 2023 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/longitudinal-recordings-of-subthalamic-local-field-potentials-show-intra-subject-consistency-of-beta-based-physiomarkers-in-parkinsons-disease/